Roofing material



Sept. 25, 1951 Filed Oct. 8, 1946 H. B. REED ROOFING MATERIAL 2 Sheets-Sheet l INVE/VTU/F HAROLD B. REED ATTORNEY Sept. 25, 1951 H. B. REED ROOFING MATERIAL 2 Sheets-Sheet 2 Filed 001:. 8, 1946 mve'wron HAPmLo' 5. R250- Patented Sept. 25, 1951 UN I TED STAT ES OF F l CE" g 1 oon-mi MAIERIAL Harold B. Reed; Hammond, lndipassignor to H;

Reedand Company, Hammond, Ind.,a part nership of Indiana Application October 8, 194 6,- seams 702,043

3 Claims.

1 o This invention relates to a new and improved roofing granule and to theimethodof manufacturing thesame and applying them to asphalt roofing, shingles, and'other articles requiring a protective coating. One feature of the invention is particularly important in the manufacture of tapered shingles whichare usually produced by longitudinally splitting a strip of roofing material which is'thickened in-the middle along a line which represents the butts of theshin'gles. It has been recognized that granular materials for roofing should embody several characteristics; for instance, it is necessary thatthe granules have suf'fic'ien't weight so as to retain the roofing in a fiat position against wind pressures to which they may be subjected. It is also necessary that the granulesbefireproof. That is to: say, that the material should be of such a character as .to be non-fusible under a temperature approximating 2000 1 It hasalso been recognized that the life of the granules shouldbe as long as possible, that they should be able to-withs'tand rough treatment, and be capable of interlocking association with the binder to hold them permanently in position;

In the prior art, it is customary to provide in the better grade of granular roofs a ceramic granular material, the base of which is usually quartz, traprock, or some other mine'mineral, which will permit a coating .of a silicious material containing pigments of different color topro viole green, blue, buff, red, white or black, ,in' all shades. In the formation of granular material of the ceramic type, the base is crushed and screened to proper size and then coated and cooked in a rotary kiln at about 1400". Ceramic granules prepared by such a method gradually fade and usually the shading is irregular, which results in a mottled appearing roof. ,.To avoid this mottled roof appearance, various blends of i several colors have been used in the industry; However, this method has not proven entirely satisfactory. It is further true in the use of ceramic granules for roofing that light reflection is notuniform inall directions, and therefore in the laying of a roof, it is necessary to use right and left shingles, this'requiring the turning of the shingles alternately end to end to provide'a uniform light reflection on the roof. To prevent confusion in this connection, the manufacturer of ceramic granular shingles-separates the rights and the lofts and ships only right shingles or left shingles to the samecustomer, and this shipping ofthe same type of shingle having" the same;-dire'cti'on or reflection" mustbe continuous; other wise, the customer may eventuallyimix the right and left shingles and thus obtain a variegated reneetienr In .th' use" of ceramic granules, it'is alsdfoiind thatthtendency in crushing the s mineral results in a flat granule body; and such.

granules are not capable of inte'rfittingl engagee, ment with each otherg wh'ich interfitting isnec-v essary' to elifninatei moisture and to protect the asphalt of the shingle; J In other granular roofing where" gravehsand; groundfbrick, -shale ,fand;simi-r lar material is used, it i found: that .such mate? rials are not impervious to. moisture, but; being mer er less poroua' absorb moisture, permitting the rrioisti'ire to: get down-Ito the iasphalt ofuthe shingle and shortening the life of thelshingle, due'to explosion 'in 'winter and general disintee, gration in heat, andat extreme heat the generatioh offsteain will cause the,..rupture of the granules from the shingle when of a porous he of th disadvantages of previously known roofing materials" has been: the comparativelyflat shape of the granule. The application ofxthe granules is'. accomplished by first coating the fibrous :base of the roofingti material with; tar or asphaltgthen sprinkling a layer; of "granules on the coating; and finally passing. a continuous sheetof th'e coated andzsprinkled fabric between rolls Whenever the thicknessfofithe granule is less than its widthgit may firstrstrikethe asphalt edgewise and then be tilted over iduring' the "rolli-; ing process so as-to leave its i opposite'Tedgerreste ing-o'n the "next. particle? Thisiocc'urs with sufli= cient frequencyito give; the roofing a combed anspea r ance and results in 1 its appearingrgnarker frornpne sidethan fioin thelothenl. This optical illusion would be "comparatively unimportant, if the shingles couldall be. eut in'the same direction, but thisj is not practical in tnemanu'facture of ta ered shingles-aud t has been consicered-necarkthe Frigh'ts and lefts and k'eep ate-,- so tha't fboth types viill not be used on the sa' e building'. g 7

Another disadvantage of 7 previously known reofiiig granmes has been the tendency' to deterie o'rate when 1 exposed" to the weather; This "is chiefly due tdthefpreseiioeof minuteeracks and fissures in tneg anules which becoine filled'with moisture v vhien fr zeS 'and splits on portions of the granules. j My praveagianui -is compara lrl r I d craks ih 'z i i s- 'and -'hasa polished, non-porous surface incapable 6f being penetrated by moisture? v V I g another {disadvantage of previbusl 'known roofing granules is matter are of'such irrgu lar shape as not to cover a sufficient percentage of the asphalt, thus leaving the asphalt exposed to the weather. My improved granule is formed in a roughly cubical shape, and the surfaces are capable of interfitting much more closely than those of previously known granules. To more specifically describe the present form of granules it might be stated that each granule comprises a multihedral structurein which the various surfaces are substantially uniform in area. The purpose of this type of granule will be obvious in.

that it provides a uniform area of contact with the roof and with the abutting or adjoining granules and eliminates a possibility of a condition which would exist should the granules be of other or irregular shapes, including thin flat slivers which are so conventional and. which result in the formation of pockets and prevent uniform adhesion. Since the granule itself is impervious to the asphalt, the asphalt is sealed in much more effectively than was the case with previous granules.

To accomplish the foregoing, the roofing granules of the present application are provided from a material and through a process which will create an individual granular element that will not fracture flat but will fracture in cubical form, will be opaque to prevent the penetration of light and yet sufliciently brilliant of surface to provide essential light reflective portions for deflecting both heat and light rays. Further, the granules to be hereinafter described, fracturing in cubical form, of necessity, provide interfitting bodies which, when applied to a surface, entirely eliminate the possibility of a porous structure, thus preventing seeping of moisture and constant deterioration in summer due to vaporization of the solvent contained in the roofing material and further eliminate the possibility of explosion of the roof surface in winter due to the freezing of moisture which might otherwise penetrate and subsequently freeze.

I have found that granules having the characteristics above outlined can be provided by the treatment of molten ash from wet bottomed powdered coal furnaces, at certain temperatures, and in an improved manner as hereinafter described. One object of this invention is to provide for the use of molten ash from wet bottomed powdered coal furnaces for the purpose of providing granules having the characteristics heretofore mentioned without interfering with the normal operation of the furnace producing the slag.

Another object of the present invention is to form a roofing shingle having a granular surface so formed and arranged that the possibility of an optical illusion is eliminated, thus avoiding expense in handling and laying of shingles.

Another object of the present invention is to provide automatic means for use in connection with wet bottomed powdered coal furnaces for providing ash granules of the type described.

Another object of the present invention is to provide an improved method of eliminating cracks and crevices in the quenched ash granules. Another object of the present invention is to so control the formation of the granules as to prevent the formation of the cylindrical sections of length greater than their diameter, which are normally present in powdered coal furnace ash and which are likely to punctur the roofing, or injure the hands of workmen.

Another object of this invention is to provide a granular roofing of such a character that the solvents of the asphalt binder are retained against evaporation due to heat, whereby the adhesive nature of the roofing is protected and the lif of the roofing substantially increased.

Other objects will more clearly hereinafter ap pear by reference to the accompanying drawings and claims.

In the drawings:

Figure 1 is a diagrammatic disclosure of an apparatus for producing the granular material.

Figure 2 is a diagram of the suspended attrition machine by which it is reduced.

Figure 3 is a side elevation of the device shown in Figure 2.

Figure 4 is a diagram showing the manner in which the shingles are coated and out.

In considering this invention, it is important to note that the term slag has been very loosely used in the various arts and has sometimes been used to describe any waste matter from a furnace. For instance, there is'slag from blast furnaces, slag from coal furnaces, and slag from any other type of furnace in which there is a burning of a mass. lSlag, in general, is not suitable for the production of granules for roofing. For instance, molten, blast-furnace slag explodes on contact with water, and produces a, spongy and frangible material totally unsuitable for the purpose. Slags from ordinary coal furnaces are also frangible and porous. Still other slags have these and additional unsatisfactory characteristics, such as fracturing flat, not sufliciently opaque, not having suitable reflective surfaces for the deflection of heat and light, and not being capable of intimate interfitted association for waterproofing.

In carrying out the present invention, applicant has learned after extensive research that the molten ash or slag from wet bottomed powdered coal furnaces, when properly treated at certain temperatures and when properly fractured, provides a granular material answering all of the requirements of the trade and all of the requirements heretofore noted as essential in the manfacture of granular roofing. The slag from the molten :ash of wet bottomed powdered coal furnaces when analyzed approximates substantially the following chemical analysis:

The slag from wet bottomed powdered coal furnaces as used in the present process for producing the granular material in question is in fact a molten ash, being substantially free of impurities such as found in conventional slag, and being purely the by-product from the burning of powdered coal in a certain type furnace.

The discharge of the slag from the wet bottomed powdered coal furnace is in a fluid state, and thi discharge from the furnace must be maintained at a predetermined constant temper'aturesothat there is substantiallymw var'ia- -tion-. in its fiuid state from its dischargefrom theifur-nace to its entry into the quenching pit, which-maybe any suitable-fluid material, but

preferably water.

The-molten ash-must be quenched' beforeit falls toofar, and any tendency to coolub'efore entering the quenching water creates a tendency of the ash to string out, these-strings-heingin:the

form ofsplines or'strings, inherently incapable ofa proper shattering andintermingling: with portions-of the slag which may properly shatter so that the entire-discharge from the furnaceiis wasted. To maintainthe fluid ash: at asuitable and uniform temperature from the. furnace. to 'the quenching water, a: heating meanslincluding i automatic controlling mechanism is hereinafter described and forms a part-of'my invention.

The type of furnace used innproducing. .the roofing granules of the application usuallyiranges in :temperature in the fireboxduring operation from e2850 F. to 3050" F.,.this -temperature being approximated at the. active: burning. level, as

measured witlranoptical pyrometer. Thetemperature of, the molten slag as.it.1eaves the furnace; ranges between .2300. F. to. .25,0( )wl and this range can be controlledpby changing burner secondary damper positions and/or alteringthe operated CO2 setting. I

A furnace capable of carrying out ,the ,method or process of producing the granulefrom the molten ash provides aadrop approximating 4: feet 4 inches from the lip of the discharge "port of the furnace to the surface of the quenching water. This distance should not. be increased and is preferably reduced. It-is. intended that thearea through which the molten ash is discharged shall be maintained constantly; at a predetermined temperature by discharging into this areasuperproduce fluid ash with different melting points and; therefore the regulation of the temperature through which the fluid ash travels must" be subjectto a predetermined; setting, whichsetting obviously should eprese t'thatj temperature producing the most'desh'able results in connection with the coal utilized in the furnace. The flow of the fluid ash will of course be at alljtirnes subject to inspection so that the desired adjustments of the temperature range may be made. It3'is obvious that the heat from the furnace proper rather than from the economizer might be used, and from whatever source the-heat is derived; it can be discharged in the area of the flowing fiuid ash. in regulated quantities by either forcedj ojr'natural draft.

The distance between the discharge point of the fluid ash in the furnace to the quenching water is of importance in that the sizeof the stream is decreased with the length offall and also with increase in temperature. When the stream is too small or too cool, there is a tendency to. formcsplinesxor icicles and the fragmentation is insufiicient. For these reasons, the-=1.

.inmarious types of furnaces, but a very satisfactory source is the molten ash as it is strained hole I2 through which the molten ash drains into a pit I3 which is filled with water to the level in- 7 reference numeral 1 patm-ofstravel'ofithefluisihi lemlls ib ma nt ined atairelativelyhigh-temperatures and these tern; :penatnresmustpeke tcons ant; It. 64%? sse tial- Ethatithe quenching, fluid '-be of such volume and depth. aSI tO produce the proper freezing of theailuid-ash. This .freezing musiq be substa'n tiallyiinstantaneous o produce ,good fragmenta tioniandgtempering. of5- the ;v particles Also, when .fluidd ashs of .the type, in ,question 1 i allowed to cool too (slowly, it becomes ll' l i or less porous land.extremely-.dullin color. An ash which cool s slowlytherefore:is-not suitable as aroofing mate;- rial; due. to aits porosity and its, lack of-color. JIhus, ;.the: discharging molten ashis keptat-a Ehighqtemperature from the point of discharge in thei furnace. to the quenching, water to; prevent prescoolinge ...It .will be apparent to .oneskilled in the jart that the granular material, due to its b; ;a1

form; providesza structure capablev of maximum cooperation with the binder and completel covers the, roofing surfaceto protect thelatter against changesintemperature and moisture, whileiat. the same time proyideslight reflection .iniallidirections, thus presenting a uniform surface color eliminatingthe, necessity of-p re -s election of shingledirection.

When the fluid ash from,.wetbottomedpow- .dered zcoal furnaces maintained at a proper. temperature. to thequenching water, it becomes Ta 'tempered iglass, very darklin color and ,very hard in substance. The strains. set up; during the .coolingua-re such that it fractures into roughly cubical pieces, mostof-which are smaller than 35 ahalfinch in diameter. The particles in this state. contain manyv incipient; fractures. but are easilmbroken down intoyery ,hardtempered particles. This material when soichilledis known as cchilled' ash,- andathisash after being properly idri'ed'sin, a rotary; kiln is crushed by suspended attritionby means; of, an-apparatus; h reinafter described. Suitable. separation, and screening. of

the: chilled ash avhen .it leaves. the attrition mill is preferably provided.

Thegranules of my invention can ,be produced from I the powdered coil boiler furnace illustrated Lby.=thedrawings/of this. application.

. Figurelisa-diagramof a furnace of this type modified: in accordance with my invention. The indicates the. combustion chamber 'which receives powdered coal through the-inlet 2 which is supplied with coal in the form of dustcarried by an air blast through the con- 'duit 3 leading from thecoal mill 4. A sectionof the coal source is indicated at 5, and the air blast is provided by a blowerindicated at 6 which receives its air-from the hot air inlet 7. This fresh air is passed through the economizer 8 and; is preheated to a high degree.

At; the top of the combustion chamber is a "slags'creen '9" above which the steam and-superheater coils IO and II are located. The inclined bottom of the furnace is provided with a drain dicated at M. The distance between the opening ouslyindicated, 'and this is 4 feet fourinches in cessfullyproduce the material. 1 I

- =The-tempe-rature in the chamber l 3 between -the hole I 2: and water level is of considerable importance. In order to maintain this temperature at tli proper level, I have provided a blower 15 which receives heated air from the economizer through an inlet is. This air may be the furnace gas, as it is very highly heated, although in some installations it will be more satisfactory to take fresh air from the conduit I after it has passed the preheating section II. The blower is pro- 'vided with an outlet conduit l8 leading into the pit l3 as indicated at l9, and the operation of the blower is controlled through a relay 20 from the thermostat 21. This thermostat may be of z-"any suitable type, and the relay may b arranged to: either cut off themotor entirely or operate it at reduced speed when the temperature in the chamber I3 suificiently high. In addition to controlling the speed of the motor 22. WhichJopI- erates the blower, a manual or thermo-control :may'be connected to the damper 23 in the coni'dlliills.

The temperature of the cooling water in the chamber I3 is also of importance. For that "reason I have provided a circulating supply pump 24 driven by motor 25 to supply water to the pit after circulating it through the cooling 'tank 26. In order to maintain a proper level of 'water, an overflow and return pipe 21' is connected to the tank 26 and provided with an inlet :28 at the desired level.

The operation of the motor 25 is controlled 'by a thermostat 29 mounted in the pit 13 below :the water level. In order to prevent overcooling of the water and thereby control its temperature, I have provided a by-pass 30 between the water return pipe 21 and the water inlet pipe 3|. This by-pass is controlled by a valve 32 which operated by solenoid 33, either in conjunction with the motor 25 or separately, as desired.

In the operation of the device shown in Fig- -.ure 1, the molten ash drains down from the (opening l2 and falls into the water where it is quenched and instantly solidified, accompanied :by fragmentation of the particles as previously described. The particles collect in the'bottom of the pin [3 and are removed through the open- 'ing 34 by means of a conveyor extending through a water seal to the atmosphere at a point above "the water level, or by any other suitable means. When the particles have been removed from the furnace pit, and dried, they contain many internal strains and have cracks and fissures which render them frangible and easily damaged by the Weather. I find that they cannot be satisfactorily reduced by the mere crushing, as this :results in the formation of ordinary crushed or broken glass particles, with so many cutting edges as to render them dangerous to handle and unsatisfactory in use. I prefer to complete the process of reduction by breaking up the mass into individual particles rather than by crushing the individual particles themselves. I find that this can be most satisfactorily accomplished by a suspended attrition process. An apparatus suitable for that purpose is shown in Figures 2 and 3.

The suspended attrition machine comprises a casing 40 formed of very heavy plate metal and containing a rotor 4| which is carried by the shaft 42 and driven by any suitable means at a speed of approximately 1,000 R. P. M. The rotor carries a number of horizontal bars or tubes 43 mounted with their axes parallel to the axis of the shaft 42. The coarse particlesare introduced by means of the cylinder 44, which hasa bent outlet 45 extending into the open end ofthe rt0 r. l

In operati dn, the particles are first caught inside the rotating bars and subjected to great impact which is sufficient to break up groups of 43 as indicated at 41. I place these rolls plates at an angle of substantially 45 to the rotor as shown in Figure 2. It will be noted that the bars are comparatively short. This length can of course be increased as desired, although it should not be excessive in view of the fact that the rotor is supported only at one end and there is no shaft bearin for the ring 48 which connects the outer ends of the bars.

Figure 4 indicates the manner in which shingles are formed by application of the granules. A strip of roofing material having a felt base or the like is indicated at 50, and moves from right to left between rolls indicated at 5|. Usually, the material comprises a single thickness, the full width shown in Figure 4 from A to B, and a second narrow thickness of the base material is attached to the main strip as indicated from C to D, this material being attached in the manner indicated and its upper surface coated with asphalt. The granules are sprinkled to the surface in an area indicated by 52, after which the granules are pressed into the surface of the asphalt by means of the rolls 5|. This results in a shingle material having a width corresponding to twice the length of the shingle. After being rolled, the shingles are formed by cutting into strips as indicated by the solid line to the left of the figure, there being four shingles to a strip with the butt ends together.

By reason of the shape of the granules of my invention, rolling them into the surface has no directional effect, and they are incapable of being tilted over with the edge of one granule on top of the next. For this reason, it is unnecessary to separate the shingles marked R and L, and they can be turned around and used side by side without any difference in their appearance.

I claim:

1. In a roofing material including a backing, a binder, and granular material carried by said binder, said granular material comprising cubical opaque granules having light reflectin surfaces and formed of slag from wet bottom powdered coal furnaces whereby heat and light deflection will be uniform in all directions.

2.'In a roofing material including a backing, a binder, and granular material formed from molten ash of wet bottom powdered coal furnaces carried by said binder, said granular material comprising granules of generally cubical form whereby interlocking association between the granules and with the binder is obtained.

3. In a roofing material including a backing sheet, a binder, and cubical granules substantially uniform in area embedded in said binder, said granules being formed from fluid ash from wet bottom furnaces by subjecting the fluid ash while in a molten state at a temperature of not less than 2300" F. to a quenching.

HAROLD B. REED.

(References on following page) REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date Morris et a1. July 24, 1866 Melvin June 27, 1871 Burnham June 9, 1874 Lowrey Mar. 30, 1915 Wagner Dec. 26, 1916 Grindle June 5, 1917 Weiss Aug. 9, 1921 Richmond et a1. Jan. 16, 1923 Number Number Name Date Williford Mar. 29, 1938 Howell Dec. 6, 1938 Kennedy et a1 Aug. 13, 1940 Smith June 24, 1941 FOREIGN PATENTS Country Date Norway Sept. 25, 1939 OTHER REFERENCES Eckel, Cements, Limes, and Plasters, 2nd ed., New York 1922, page 455.

Gibson 81 Selvig, Rare and Uncommon Chem. Graveman Nov. 29' 1927 15 Elements m Coal, Washington 1944, page 2, 

1. IN A ROOFING MATERIAL INCLUDING A BACKING, A BINDER, AND GRANULAR MATERIAL CARRED BY SAID BINDER, SAID GRANULAR MATERIAL COMPRISING CUBICAL OPAQUE GRANULES HAVING LIGHT REFLECTING SURFACES AND FORMED OF SLAG FROM WET BOTTOM POWDERED COAL FURNACES WHEREBY HEAT AND LIGHT DEFLECTION WILL BE UNIFORM IN ALL DIRECTIONS. 